Sonnenschein Bonnie, Conover Kent, Shizgal Peter
Department of Psychology, Center for Studies in Behavioural Neurobiology, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6, Canada.
Behav Neurosci. 2003 Oct;117(5):978-94. doi: 10.1037/0735-7044.117.5.978.
The strength of a train of rewarding brain stimulation required to support a criterion level of operant performance declines hyperbolically as the duration is increased. This finding has been attributed to a process of leaky integration. However, the rate at which integration approaches asymptote has been shown to depend on stimulation strength, a finding that differs from the behavior of a simple leaky integrator. The authors replicate both findings and show that they are both well described by a new model that incorporates a hyperbolic strength-duration function, a logistic function mapping stimulation frequency onto reward intensity, and another logistic function mapping reward intensity onto performance.
为维持操作性行为表现的标准水平所需的一系列奖励性脑刺激的强度，会随着刺激持续时间的增加呈双曲线下降。这一发现被归因于一种漏积分过程。然而，已有研究表明，积分趋近渐近线的速率取决于刺激强度，这一发现与简单漏积分器的行为不同。作者重复了这两项发现，并表明它们都能被一个新模型很好地描述，该模型包含一个双曲线强度-持续时间函数、一个将刺激频率映射到奖励强度的逻辑函数，以及另一个将奖励强度映射到行为表现的逻辑函数。
